Carburetor off idle stumble

Author: hoyn

August undefined, 2024

WebOct 22, 2001 · Well I finally tried something that totally fixed the stumble problem and made the car go faster at the same time. I yanked the MF Holley carb off and put my 10 year … WebFeb 19, 2012 · We transferred the new Edelbrock intake and carb to the new engine. Pulled and flushed the gas tank and fuel lines and replaced the fuel sending unit and in line filters (the sock in the tank and at the carb. Still have the same problem. She stumbles and hesitates under normal acceleration. Nothing aggressive, just pulling off from a stop, like ...

Carb Science Series: Carb Tuning for Big-Cam Engines

WebJun 25, 2007 · Hey guys just threw a speed demon 850 dbl pumper (slightly used) on my BBC. Works great except for the ever popular "off-idle stumble" during "light" … WebFeb 5, 2024 · John D - the idle tubes in a Rochester 4GC are the outer (small) tubes pressed into the underside of the primary venturi cluster. The Doug Roe book on Rochester carburetors is helpful in nomenclature. As to drilling, as the hole is very small; best to use a "pin vise" and a drill from a 61~80 numbered drill set. small town cleaners

Brawler Carburetor Help Needed 460 Ford Forum

WebMar 10, 2013 · Its a Edelbrock 1406 model. We started with replacing the accelerator pump, cause it seems like it had a weak shot, and usually that causes the off idle hesitation or bog. No dice. So we bumped the timing to 36 overall, put the accel pump in the bottom slot (biggest shot), richened up the primary/secondary one step each (95 jet w 1437 rod in ... WebNov 17, 2024 · Discussion Starter · #1 · Nov 15, 2024. I'm looking for some carburetor tuning assistance. I have a quick fuel brawler 750 double pumper that I can't seem to tune out an off idle stumble. This carb is on a 460 in a 77 f150 4wd manual trans truck. Engine setup is a 72 block zero deck kb flat top bottom end. Heads are stock 429 PI. WebAug 7, 2006 · He has a new holley 4160 750 cfm DP carb. The car has a terrible stumble off of idle. You could almost stall the car with it if you held your foot there. I read every post using the search function i could find. The accel pump squiters look and work fine. We have opened the carb up and all passages look fine. The timing has been checked and ... highways hotel springvale

Edelbrock 1406 WOT bog/stumble--how I fixed mine...

How To Cure Carburetor Stumble - Holley Motor Life

WebDec 13, 2004 · Location. mid-west U.S.A. Dec 9, 2004. #43. jokers said: I hate to admit it, but I have it on good authority that the green cap 359 has a low speed carb orifice of about .019 while the 346 has a low speed orifice of .030, of course it is going to be harder to start. What anyone with one of these saws needs is for Stihltech to hack it for you, LOL. WebMar 20, 2010 · 818 Posts. Discussion Starter · #3 · Mar 18, 2010. ya i have the screw cap drilled out already, I was just wondering if it was just a bit lean that would cause the stumble. Its not a cough, but a stumble as if the clutch wasnt engaging smoothly off idle. when riding shifting is smooth. small town clothing companyWebJun 26, 2007 · just threw a speed demon 850 dbl pumper (slightly used) on my BBC. Works great except for the ever popular "off-idle stumble" during "light" acceleration. Not sure … small town club

"WebDec 4, 2024 · Holley recommends the No. 1 position for idle speeds below 900 rpm and suggests moving to the No. 2 position for engines that idle above 900 to 1,000 rpm. … " - Carburetor off idle stumble

Carburetor off idle stumble

Holley 885 Idle Circuit - carburetor-parts.com

WebJul 5, 2024 · Aside from a little lean off idle stumble, its been fine so far. Today, I get gas (my second tank since the carb install) & all of a sudden, motor feels like it wants to die, idle is down from 750 or so to 500 & when I stab the throttle the motor feels like it … WebThere are 2 idle passages on the Holley 885, one for each barrel. At idle, the normal air pressure in the float chamber causes fuel to flow through the idle system to greatly reduced pressure area below the throttle plates. Fuel flows from the float chamber through the main jet and into the bottom of the main well.

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WebAug 13, 2008 · western star. I have an Edelbrock 600 carb that's about 4 years old. I get a slight stumble when I take off and sometimes when you increase the throttle from a cruise speed. I notice a little moisture around the accelerator pump rod but not a lot. I have disconnected the choke and wired it open just to see if the choke had anything to do with it. WebApr 4, 2013 · If you loosen the screws on the front of the carb at the base plate 1/4 turn and it doesn't change idle speed, go back in and go 1/4 turn tighter than when you started to …

WebMay 6, 2024 · Later our friend noticed that no amount of idle mixture tuning improved the car’s tendency to run rich. Worse yet, any attempt at leaning the idle mixture only worsened a disagreeable off-idle stumble. Our friend liked the way the engine sounded at idle, but he hated the way it ran most of the time and how quickly it fouled spark plugs. WebJun 17, 2012 · Jul 18, 2011. 16. MN. I have an off idle stumble with my Edelbrock carb and cant seem to cure it. I am using an Innovate LM2 to help tune, everything is fine @ idle, …

WebDec 4, 2007 · Most people experiencing hesitation think, "put in bigger jets" right off the bat. Well, forget that silly notion, the jets have nothing to do with it. A light stumble only when … WebSep 5, 2007 · nexxussianMemberfrom Anchorage, Alaska. Idle screw should be fuel, counterclockwise is more fuel (richer) clockwise is less (leaner). The only carbs I have come across that have air screws for idle (on cars) are some Holleys off a 70's smog POS. nexxussian, Sep 5, 2007. SHARE POST #22.

WebJul 7, 2024 · After buying the Summit 600 cfm version (SUM-M08600VS) and reading some old posts here it looks like I may have been better off with the 500 cfm version, but it sounds like a 600 can be tuned to work fine with a 289. After installing it, it cranks perfectly every time, and I have it idling very well. About 17 in of stable vacuum, and around 750 ...

WebJul 5, 2012 · If your car or truck is equipped with a Holley four barrel carburetor and stumbles upon acceleration, more than likely the carburetor needs an adjustment to the accelerator pump assembly. This assembly delivers an initial shot of fuel in the right … highways hotel sandownWebOct 13, 2013 · THEN dial the carb circuits (idle, power and cruise) individually to correct AFRs THEN establish independently your dizzie tuning specs (idle advance, total advance, VA degs, VA vaccuum start and finish pionts) locking the the cent weights. ... Off idle stumble is gone, idle is good, at 950 rpm, and sounds great. Two things i found as well ... highways hotlineWebAug 20, 2013 · goldduster318. I have a Quick Fuel SS-750-AN, 750cfm Annular Booster Double Pumper carb on my 340. This carb seems to run great in all areas except right off of idle and if you get into the throttle a little bit at low RPM in 4th gear. The car is a '70 Duster, full weight, 4-speed, and 3.23 gear. Fuel Pressure is 6 psi with a regulator and the ... small town clueWebJan 28, 2008 · Engine will stumble and/or die. Test two, just disconnect the valve and drive the car to see if it is better. More than likely, if the carb was set to the old motor, and you made changes to the new 355, it is more likely just lean. You might try opening the idle mixture screws a bit to see if the problem gets better. What carb are you using? highways hounslowWebMay 30, 2008 · A carb running rich, as well as a carb running lean, can cause an off-idle stumble or hesitation upon acceleration. To narrow it down, tap the roll pin out of the accelerator pump lever by using a small pin punch or a small finish nail. I actually use a small, broken drill. bit that’s just the right size. small town clothingWebSep 1, 2004 · The answer is amazingly simple. The first result of a long-duration camshaft with lots of overlap is drastically reduced idle vacuum. Instead of 16 to 18 inches of … highways house caerphillyWebJan 25, 2024 · Power valve is probably opening because that rough idle camshaft is only allowing the motor to make 4 or 5 inches of vacuum….if that’s the case try a 3.5 valve if … small town clothing store